https://doi.org/10.1140/epja/s10050-022-00722-w
Regular Article - Theoretical Physics
Azimuthal-sensitive three-dimensional HBT radius in Au–Au collisions at 
GeV by the IQMD model
1
Shanghai Institute of Applied Physics, Chinese Academy of Sciences, 201800, Shanghai, China
2
University of Chinese Academy of Sciences, 100049, Beijing, China
3
Key Laboratory of Nuclear Physics and Ion-beam Application (MOE), Institute of Modern Physics, Fudan University, 200433, Shanghai, China
4
Shanghai Research Center for Theoretical Nuclear Physics, NSFC and Fudan University, 200438, Shanghai, China
Received:
17
November
2021
Accepted:
3
April
2022
Published online:
30
April
2022
We used an Isospin dependent Quantum Molecular Dynamics (IQMD) model to simulate Au + Au collisions at beam energy 
= 1.23A GeV, which corresponds to center of mass energy 
GeV. Firstly, we obtained reasonable rapidity and transverse mass spectra of 
and 
as well as “apparent” temperature parameters in comparison with the HADES data. Then by calculating three-dimensional Hanbury Brown and Twiss (HBT) radius of same charged pion-pairs, we obtained the square difference of outward radius and sideward radius, i.e. 
, as well as the freeze-out volume (
), which were basically consistent with the trend of HADES experimental results. The azimuthal dependence of the HBT radii was also calculated by a matrix method, and corrected by the rotation matrix. In addition, the eccentricities of the xy- and zy- planes of pion-pair emissions were also extracted for different pair transverse momentum and collision centrality, which show that the xy-eccentricity increases with pair transverse momentum as well as centrality but not for zy-eccentricity, indicating a more asymmetric transverse emission of particle-pairs with higher transverse momentum in off-central collisions.
© The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2022
